1 # no need for shebang - this file is loaded from charts.d.plugin
3 # if this chart is called X.chart.sh, then all functions and global variables
6 # _update_every is a special variable - it holds the number of seconds
7 # between the calls of the _update() function
10 # the priority is used to sort the charts on the dashboard
12 example_priority=150000
14 # to enable this chart, you have to set this to 12345
15 # (just a demonstration for something that needs to be checked)
18 # global variables to store our collected data
19 # remember: they need to start with the module name example_
28 # do all the work to collect / calculate the values
32 # 1. KEEP IT SIMPLE AND SHORT
33 # 2. AVOID FORKS (avoid piping commands)
34 # 3. AVOID CALLING TOO MANY EXTERNAL PROGRAMS
35 # 4. USE LOCAL VARIABLES (global variables may overlap with other modules)
37 example_value1=$RANDOM
38 example_value2=$RANDOM
39 example_value3=$RANDOM
40 example_value4=$((8192 + (RANDOM * 16383 / 32767) ))
42 if [ $example_count -gt 0 ]
44 example_count=$((example_count - 1))
46 [ $example_last -gt 16383 ] && example_value4=$((example_last + (RANDOM * ( (32767 - example_last) / 2) / 32767)))
47 [ $example_last -le 16383 ] && example_value4=$((example_last - (RANDOM * (example_last / 2) / 32767)))
49 example_count=$((1 + (RANDOM * 5 / 32767) ))
51 [ $example_last -gt 16383 -a $example_value4 -gt 16383 ] && example_value4=$((value4 - 16383))
52 [ $example_last -le 16383 -a $example_value4 -lt 16383 ] && example_value4=$((value4 + 16383))
54 example_last=$example_value4
57 # - 0 to send the data to netdata
58 # - 1 to report a failure to collect the data
63 # _check is called once, to find out if this chart should be enabled or not
66 # - 0 to enable the chart
67 # - 1 to disable the chart
70 [ "${example_magic_number}" != "12345" ] && echo >&2 "example: you have to set example_magic_number=$example_magic_number in example.conf to start example chart." && return 1
72 # check that we can collect data
73 example_get || return 1
78 # _create is called once, to create the charts
80 # create the chart with 3 dimensions
82 CHART example.random '' "Random Numbers Stacked Chart" "% of random numbers" random random stacked $((example_priority)) $example_update_every
83 DIMENSION random1 '' percentage-of-absolute-row 1 1
84 DIMENSION random2 '' percentage-of-absolute-row 1 1
85 DIMENSION random3 '' percentage-of-absolute-row 1 1
86 CHART example.random2 '' "A random number" "random number" random random area $((example_priority + 1)) $example_update_every
87 DIMENSION random '' absolute 1 1
93 # _update is called continiously, to collect the values
95 # the first argument to this function is the microseconds since last update
96 # pass this parameter to the BEGIN statement (see bellow).
98 example_get || return 1
100 # write the result of the work.
102 BEGIN example.random $1
103 SET random1 = $example_value1
104 SET random2 = $example_value2
105 SET random3 = $example_value3
107 BEGIN example.random2 $1
108 SET random = $example_value4
111 # echo >&2 "example_count = $example_count value = $value4"